The treatment of fibrous substrates with fluorochemical compositions to impart water and oil repellency is known; see, for example, Banks, Ed., Organofluorine Chemicals and Their Industrial Applications, Ellis Horwood Ltd., Chichester, England, 1979, pp. 226-234. Such fluorochemical compositions include, for example, fluorochemical guanidines (U.S. Pat. No. 4,540,497), compositions of cationic and non-ionic fluorochemicals (U.S. Pat. No. 4,566,981), compositions containing fluorochemical carboxylic acid and epoxidic cationic resin (U.S. Pat. No. 4,426,466), and fluoroaliphatic alcohols (U.S. Pat. No. 4,468,527).
Additives have been employed to assist in the oil and water repellency of fluorochemical treating agents.
U.S. Pat. No. 4,215,205 discloses combinations of fluorochemical vinyl polymer and carbodiimide in compositions said to impart durable water and oil repellency to textiles. Some of the carbodiimides disclosed contain fluoroaliphatic groups.
U.S. Pat. No. 5,132,028 discloses compositions for imparting water and oil repellency to fabrics such as silk, said compositions containing a fluorochemical-type, water and oil repellent agent, a carbodiimide, and at least one component selected from the group consisting of plasticizer, metal alcoholate or ester, zirconium salt, alkylketene dimer, aziridine, and alkenyl succinic anhydride.
U.S. Pat. No. 3,955,027 discloses an improved process and composition for water and oil proofing textiles which comprises treating a textile with a polymeric fluorocarbon finishing agent and at least one reactive polymer extender having acid or anhydride functionality and curing the treated textile at from 80.degree. C. to 170.degree. C. for 0.1 to 60 min. The reactive polymer extenders are low molecular weight polymers having a molecular weight of less than about 8000.
U.S. Pat. No. 4,070,152 discloses compositions comprising a textile treating resin which is a fluorine-containing polymer and a novel copolymer of a maleic-anhydride copolymer and a fatty acid amine and an amino organo polysiloxane. Said compositions are useful for increasing the water and oil repellency of substrates such as textiles, paper, or leather.
WO 93/01348 discloses aqueous treating compositions for providing water and oil repellency, stain resistance and dry soil resistance which comprise
a) 0.3 to 30% by weight of a water soluble or dispensable fluoroaliphatic radical-containing polyoxyalkylene compound; PA1 b) 0.3 to 30% by weight of an anti-soiling agent, and PA1 c) water. The anti-soiling agent may include i.e., styrene-maleic anhydride copolymers and vinyl acetate-maleic anhydride copolymers. PA1 (a) a fluoroaliphatic radical-containing agent; and PA1 (b) a polymer comprising cyclic carboxylic anhydride groups, PA1 R.sub.f is a fluoroaliphatic radical; PA1 R.sup.1 is an alkylene with, for example, 1 to 10 carbon atoms, e.g. methylene or ethylene, or is --CH.sub.2 CH(OR)CH.sub.2 --, where R is hydrogen or --COCH 3; PA1 R.sup.2 is hydrogen or methyl; PA1 R.sup.3 is hydrogen or an alkyl with, for example, 1 to 10 carbon atoms, e.g. methyl or ethyl; and PA1 R.sup.4 is an alkylene with, for example, 1 to 10 carbon atoms, e.g. methylene or ethylene.
Although water and oil repellent treating agents are readily available, it is well known that they are expensive. Also, the efficiency in water and/or oil repellency is not always satisfactory. Furthermore, when they are employed for the treatment of textiles, they suffer from the disadvantage that they tend to give the treated textile a hard feeling. In order to overcome this problem, silicone softeners are commonly applied. However silicones are usually not compatible with the fluorochemical treating agent, and therefore, the treated substrates typically will show a decrease in water and oil repellency.